170 A TEXT-BOOK OF BOTANY 
it, one of them fuses with the egg, and an oospore is 
formed. It is evident that fertilization can take place 
only in the presence of moisture. 
Fic. 166.—M archan- 
tia: archegonium, 
Fic. 165.—MJurchantia: A, thallus bearing archegonial containing an egg; 
branches of various ages; B, section through portion of sperms seen at the 
archegonial disk, showing pendant archegonia.—After mouth of the neck. 
Ky. — After Kny. 
95. The spore-case.—As soon as the odspore is formed 
it begins to germinate; but instead of forming a new Alar- 
chantia thallus, it produces a very 
different structure. The odspore 
germinates just where it was formed, 
that is, in the bulbous base of the 
archegonium; and there the new 
structure grows. When it is fully 
developed it is seen to consist of a 
ee i) Aovedbiadine ahs do terminal spore-case full of spores, 
rophyte formed within the and a sterile base (Fig. 167, A). 
enlarged archegonium, show- . : : 
ing the spore-bearing (a) and While growing, this Spore-case be- 
sterile (6) regions; B. spore- eogmes anchored in the Marchantia 
ease discharging spores, the 
sterile region of the sporo- body (that is, in the archegonium- 
phyte having developed into - ° “ 
a stalk.—After Ky. bearing disk) by the sterile base, 
Mt 
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